I have owned a pair of RM Stockyard boots for at least 30 years. Haven't flown for 10 years but took them out for a walk recently Soles still looked brand new but soon suffered flap flap of heel. The inside of both boots soles and heels were rotten I tried gluing them back together but was gluing one good bit to a rotten one. Couldn't bear to throw them away so went looking for a proper cobbler. (Rare as rocking horse dung). 75 quid for new Vibram soles and heels and the boots look almost new. I suspect they will outlast me. The cobbler is in a garrison town and does a roaring trade. Not only competent but reasonably priced.